慈菇黑粉病又称古疱病,是由真菌所致的病害,近年来,在慈菇产区有逐年加重为害的趋势,是严重制约慈菇优质高产的重要因素,发病后,一般减产20%左右,严重的达30%以上。一、发生规律:一般由种子带菌传染,因而,用慈菇的病芽作种时发病程度加重,病菌侵入寄主的最适温度为18-20℃,但病菌侵入寄主后至发病时,则要求高温,以26-28℃病害发展最快。高温高湿最易发病。一般7月中、下旬降水天数超过5天,气温在28℃左右时,有利于病菌的繁殖和侵入,常导致病 Mushroom powdery mildew, also known as ancient blister disease, is a disease caused by fungi. In recent years, there is a tendency of increasing year by year in Sagittaria indica area, which is an important factor that severely restricts the quality and high yield of Sagittaria indica. 20% or so, serious up to 30% or more. First, the occurrence of law: the general infection by the seed carrier, therefore, with the mushroom seedlings for the disease when the incidence increased, the optimum temperature of invasion of host bacteria 18-20 ℃, but the invasion of pathogens after the onset of the host, it is required High temperature, the fastest development of disease at 26-28 ℃. Hot and humid the most vulnerable to disease. Generally in mid-July, the precipitation days more than 5 days, when the temperature is about 28 ℃, conducive to the breeding and invasion of bacteria, often leading to disease